Résumé / Abstract Journal-club_Doctorants

Séminaire Doctorants / Seminar PhD students

« Missing energy in the radio-emission of particle cascades »

Simon Chiche
Institut d'Astrophysique de Paris (Paris, France)

In this talk I will mainly give a more complete overview of the topic I presented
at the PhD day so the abstract is the same!

What is the origin of ultra-high energy cosmic-rays, these charged atomic nuclei
that arrive on Earth with energy > 10^18 eV? To collect enough particles and
solve this mystery, observatories covering gigantic surfaces have to be built, using efficient detection techniques. Radio detection, i.e., the detection of radio signals from the particle cascades (air-showers) that ultra-high energy particles induce in the atmosphere, is a robust, efficient, scalable and hence promising technique.
Cascades induced by particles with inclined arrival directions are of particular
interest as they exhibit a large footprint that allows to sample the signal with only few antennas. The construction of several of such large-scale radio-detectors
focusing on inclined air-showers are being currently planned (GRAND,
BEACON, GCOS). However, the physics of the radio emission of very inclined
air-showers is scarcely understood, and needs to be explored with analytical and
numerical methods. In the preparation for these large-scale radio-experiments I
have developed an innovative fast semi-analytical simulation tool for very
inclined air-showers. This tool relies on a deep understanding on the radio signal
polarisation and enabled us to identify a new radio emission signature, specific
for inclined air-showers, in a new regime that was not described by any model.
The understanding of this regime would be a major advancement toward this new
era of large-scale UHE astroparticle detection.
vendredi 29 avril 2022 - 16:00
Salle Entresol Daniel Chalonge, Institut d'Astrophysique
Page web du Séminaire / Seminar's webpage